MT93L04AG Zarlink Semiconductor, MT93L04AG Datasheet - Page 37

• Manufacturer Part Number: MT93L04AG
• Description: Description = 128-Channel Voice Echo CANceller ;; Package Type = Bga ;; No. Of Pins = 365
• Manufacturer: Zarlink Semiconductor

Preliminary Information
Echo Canceller A, Noise Scaling (NS)
Echo Canceller B, Noise Scaling (NS)
Echo Canceller A, Injection Rate (IR)
Echo Canceller B, Injection Rate (IR)
Echo Canceller A, Rin Peak Detect Register 2 (RP)
Echo Canceller B, Rin Peak Detect Register 2 (RP)
If the comfort noise level estimator is unable to correctly match the background noise level, this register
can be used to scale the comfort noise up or down. A neutral value of 80h will prevent any scaling.
Values less than 80h will scale the comfort noise level down. Values greater than 80h will scale the
comfort noise level up. Scaling is done linearly, so to scale the comfort noise down by 1 dB, a value of
72h would be used (-1 dB = 89% of original level, 0.89
use a value of 8Fh (1 dB = 112% of original level, 1.12
The NLP ramps-in comfort noise during the initial background noise estimation stage. This register
provides control over the ramp-in speed. Higher values will increase the ramp-in speed.
These peak detector registers allow the user to monitor the receive in signal (Rin) peak signal level. The
information is in 16-bit 2’s complement linear coded format presented in two 8 bit registers for each echo
canceller. The high byte is in Register 2 and the low byte is in Register 1.
Echo Canceller A, Rin Peak Detect Register 1 (RP)
Echo Canceller B, Rin Peak Detect Register 1 (RP)
RP15
RP7
NS7
IR7
7
7
7
7
RP14
RP6
NS6
IR6
6
6
6
6
RP13
NS5
IR5
RP5
5
5
5
5
RP12
NS4
IR4
RP4
4
4
4
4
RP11
NS3
IR3
RP3
3
3
3
3
RP10
NS2
IR2
RP2
2
2
2
2
NS1
IR1
RP9
RP1
1
1
1
1
(dec)
(dec)
• 80h = 8Fh).
NS0
• 80h = 72h). Similarly, to scale up by 1 dB,
IR0
RP8
RP0
0
0
0
Read/Write Address:
Read/Write Address:
0
Read/Write Address:
Read/Write Address:
Read Address:
Read Address:
Read Address:
Read Address:
0Dh
2Dh
0Ch
2Ch
0Bh
2Bh
0Ah
2Ah
+ Base Address
+ Base Address
+ Base Address
+ Base Address
+ Base Address
+ Base Address
+ Base Address
+ Base Address
Power Reset Value
Power Reset Value
Power Reset Value
Power Reset Value
0Ch
74h
N/A
N/A
MT93L04A
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